replacing value only from an Xelement using linq

Question

EDIT: A bit more detailed HTML document... In short- how do I actually do the lookup and where precisely should the element.setvalue or element.value appear in the query...

Edit 2: The list of monkey id does not appear clear so I will add proper id's and add additional properties to my Lookup data object, sorry for the confusion! The reason I have used a list is bacause my datasource could be from anywhere also I have used a List object because I do not really know the proper usage of Dictionary (I am a newbie to coding hence why my question is all over the place, please bear with me)

I have an XElement which is a properly formatted HTML document, I am trying to replace only the value of a html element with a value contained in a List Object for example

<div id="pageContainer">
<p> some guy wants to <b>buy</b> a <h4><label id="monkey23">monkeyfield</label></h4> for some price that I do not have a clue about, maybe we should <i>suggest</i> a list of other monkeys he may like:
</p>
<h3>list of special monekeys you may want chappy...</h3>
<br />
<ul>
    <li><label id="monkey13">monkeyfield</label></li>
    <li><label id="monkey3">monkeyfield</label></li>
    <li><label id="animal4">animalfield</label></li>
    <li><label id="seacreature5">seacreaturefield</label></li>
    <li><label id="mamal1">mamal field</label></li>
</ul>
</div>

Note: the value "monkeyfield" is a temporary value inserted onscreen for the purpose of identifying this is a field, once the values from the data source is binded the new values should appear.

public class LookupData
{
  public string id{get;set;}
  public string value{get;set;}
  public string Type{get;set;}
  public string Url{get;set;}
}

...    
public void DataTransformerMethod()
{
 var data = new List<LookupData>();
 data.add(new LookupData{id="monkey3", value="special monkey from africa" });
 data.add(new LookupData{id="monkey13", value="old monkey from china" });
 data.add(new LookupData{id="seacreature5", value="sea monkey" });
 data.add(new LookupData{id="animal4", value="rhino" });
 data.add(new LookupData{id="mamal1", value="some mamal creature" });
 //what linq query will iterate over the document and set the values from the values
 //found in the list?

       var answer = from x in HtmlDocAsAXelement
                    where x.Attributes()
                    .Any(a=> data.AsEnumerable().Where(f=> f.Name == a.Name) );
//somehow I should use .SetValue(a.value)???

SaveTheNewXElement(answer ); //all other original data must stay in tact...

}

Answer 1

Well, you need to iterate over all the XElements which need changing - and set their value by just calling the Value setter:

element.Value = "newvalue";

It would be trickier if the element had multiple text nodes and you only wanted to change one of them, but as there's no other content within the element, this should be fine for you.

EDIT: After the discussion, I would do something like this:

Dictionary<string, string> replacements = data.ToDictionary(x => x.id,
                                                            x => x.value);

foreach (XElement element in HtmlDocAsAXelement.Descendants())
{
    string newValue;
    string id = (string) element.Attribute("id");
    if (id != null && replacements.TryGetValue(id, out newValue))
    {
        element.Value = newValue;
    }
}

Answer 2

You can't do that "easily", because there is no foreach equivalent in LINQ. That's on purpose. See http://blogs.msdn.com/b/ericlippert/archive/2009/05/18/foreach-vs-foreach.aspx and LINQ equivalent of foreach for IEnumerable<T>.

I would suggest you just do a normal foreach over the query results.